Nope, you understand wrong.Master Chief once bubbled...
Now my understanding is that the GAVIN is more suitable for cave divers etc...
Heres a page to poke around, lots of pictures of Gavins being used in open water (San Francisco area):
http://www.baue.org/
This video on this page will show you that the prop wash goes beneath you:
http://www.gue.com/equipment/feature/gavin/feature.shtml
Also notice with the prop out in front, unlike the Farallon, your equipment wont be swept back by the current into the blades and you can keep an eye on the blades. The Farallon requires you to do isometric exercises throughout the dive (hanging on, which expends energy then therefore burns gas) whereas the Gavin tows you, saving gas energy and reducing fatigue.
The Gavins were used extensively for the Britannic expedition:
http://www.gue.com/research/britannic/index.shtml (follow the Gallery link)
The only dissenting opinion, AquaTec, has referred to a Gavin copy (Im assuming you meant Silent Submersion):
http://www.silent-submersion.com/
You asked, you got a unanimous NO for the Farallon and a yes for the Gavin (with one vote for a copy). Did you really want help with your choice or simply confirmation that you made the right choice (which you didnt get)? This board is a wealth of information, but only if you use it.
Roak